A heterocyclic compound configures a basic skeleton of a natural material, and an organic phosphorus compound has pharmacological and physiological activities. The organic phosphorus compound is significantly associated with biological phenomena, such that developments of and researches into various synthesis methods have been conducted depending on novel physiological activities thereof. Particularly, in an organic phosphorus compound having a structure similar to carbon in organic compounds, chemical reactivity and physiological activity of phosphorus have been spotlighted.
Particularly, since a benzoxaphosphole 1-oxide compound, which is one of the phosphorus heterocyclic compounds, has physiological activity and may be used in synthesis of a novel medicine, it is important to develop a synthesis method thereof. Therefore, various researches for developing a synthesis method of benzoxaphosphole 1-oxide derivatives as described above have been reported (J. Org. Chem. 1982, 47, 1677).
In addition, a dihydro-azaphosphole 1-oxide derivative is heterocyclic compounds used as a crop protecting agent, but research into a preparation method of the dihydro-azaphosphole 1-oxide derivative has not frequently reported, and research into properties of the compound itself has not also frequently conducted, such that research into the dihydro-azaphosphole 1-oxide derivative has been demanded. As the existing reported synthesis method of a dihydro-azaphosphole 1-oxide derivative, a synthesis method using an intramolecular annulation reaction of 2-chloromethylphenylphosphinamide in the presence of 1,5-diazabicyclo-[4.3.0]non-5-ene, a synthesis method of a nucleophilic substitution reaction between multi-substituted phosphonic dichloride and a benzylamine derivative substituted with lithium, a synthesis method using a photo-decomposition process from a dimesitylenephosphinic azide derivative and an intramolecular cyclic reaction have been reported (J. Chem. Soc., Chem. Commun. 1991, 1187; J. Org. Chem. 1981, 46, 3486; U.S. Pat. No. 4,272,278A). However, in the reported synthesis methods, it is impossible to introduce a substituent at a third position of dihydro azaphosphole 1-oxide derivative, and a reaction step of introducing halide should be performed, such that these methods are uneconomical.
A synthesis method of a novel dihydro-1H-phosphole 1-oxide derivative using an olefination reaction through a carbon-hydrogen bond activation reaction of phosphonic monoester or phosphonic amide, which is a phosphonic derivative according to the related art, and a vinyl derivative and a subsequent annulation reaction has not yet been reported. Therefore, the development of a novel synthesis method of various dihydro-1H-phosphole 1-oxide derivatives using these reactions has been demanded.